inspect_mime_magic_bytes

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden. It discloses that the tool inspects the first 512 bytes, ignores extensions, and requires a 0.005 USDC micropayment on Base L2. It does not mention output format, error behavior, or whether the tool is read-only, leaving some behavioral gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, tightly packed sentence that leads with the core purpose and appends the cost in parentheses. Every word earns its place; there is no fluff or repetition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple, but with no output schema, the description must explain what the tool returns and how to provide the payload. It only says 'identifies true file format' without specifying the output MIME type or the payload format (base64 vs raw bytes). For an agent to call this correctly, that information is essential, making the description incomplete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, but parameter descriptions are generic ('Input parameters or JSON string payload'). The description adds that payload is the binary data to inspect, but does not specify encoding (e.g., base64, file path), which is critical for correct invocation. It adds some value beyond the schema but not enough to fully clarify parameter usage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool identifies true file format from binary magic bytes, specifying the scope (first 512 bytes) and the key differentiator (ignoring spoofed file extensions). This distinguishes it from siblings like validate_code_syntax or convert_svg_to_png without ambiguity.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies the use case: when you need to determine the real file type despite a misleading extension. However, it doesn't explicitly state when not to use it or mention alternative tools for similar tasks, leaving the routing decision mostly to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.